need help car wont start and if it does it has low idle or dies

[hks_97gst]

hey guys, i have a 97 GS-T w/ HKS intake, greddy hard intercooler pipping, greddy type-s bov, and HKS turbo timer

and I've tried to search for a similar problem but i cant find one and i need to figure this out as soon as i can!

well its really weird, one night i was driving to the gas station and i went inside, and when i came out to start my car i turned to the first accessory the CD player would come on, then i turned it to the second one where my turbo timer usually comes on and it didn't, so i put the clutch in and i went to start it but when i did, all the lights, and electronics, CD player would all just shut off. and then i tried to jump it and it worked but as soon as i backed the car up and i put the clutch in the rpms dropped and it died. so i ended up trying out the battery in my friends car and his started right up, so its not dead, and I've had it tested.
so i put it in my car and then it started up but i had to keep the rpms up so it wouldn't die.
well the next morning it started up fine and i took it to wall mart and the charging system checked and it was good, and the car worked perfectly for the next week

well then it happened again but we took out the battery to get it tested and as i said it was good so all we did was put it back in and it worked but on my way home every time i disengaged the clutch or put it in neutral, the rpms would drop to the bottom and the lights would dim and i thought it was dead but i would touch the gas and it would barely com back but i would have to hold the rpms up.

sorry for the long post but i wanted to give you guys all the info does anyone have any idea what would cause this? any help is greatly appreciated! since this is my daily driver and only car. thanks

 

[ddavisaf]

Don't appologize for the length of your post. The more information you can give us the better.
It sounds like your ISC is going bad.
http://dmtalon.v8eaters.com/ISC.html

 

[hks_97gst]

thanks for your reply ddavisaf, but do you also think there is another reason for it not wanting to start, because that is what confuses me the most, and i forgot to mention that when it happened the second time and i tuned the radio on, i turned on the reading light and at the same time the radio turned off then i shut off the light and the radio turned on and then off then on then off for a minute all by its self so then i turned it one more click but the turbo timer didn't turn on, so i turn it all off and take the keys out and then the turbo timer starts counting down WTF so i don't understand it at all.

but thanks for the info on the isc maybe it is the problem

but why does power shut off when it should start and then go crazy like that? does any one know if it might be an ignition problem or signs of a bad ecu, or a short in the wiring?

 

[ddavisaf]

It's signs of a bad ECU or a short. Chances are a bad ECU. After you inspect for leaking caps I'll throw you the link on how to check for shorts.

 

[hks_97gst]

u mean leaking caps in the isc?

 

[ddavisaf]

No in the ECU.
Your idle surge is most likely caused by a bad ISC, everything else by a bad ECU. Test the ISC first. Then check the caps in the ECU.

 

[ddavisaf]

http://simon.chi.il.us/~steve/Auto/DSM/ECURepair.html
I send my ECU to steve if I have a problem with it. Only person I trust.

 

[hks_97gst]

thanks ill get back to you as soon as i can test it

 

[hks_97gst]

hey I'm borrowing a friends multimeter tomorrow, then i can test the isc. and is the tps(throttle position sensor) the same thing as the isc and if it isn't where can i get a isc?
and where are the caps on the ecu does anyone have a picture? and by caps do you mean capacitors? what does caps specificly mean?

thanks for the help!

 

[ddavisaf]

http://www.tmo.com/howto/ecu1g/caps.htm
Capacitor replacement guide, I still recommend sending it to steve though.

ISC testing....
http://dmtalon.v8eaters.com/ISC.html

TPS Adjustment
http://www.plymouthlaser.com/tps.htm

 

[hks_97gst]

well i tested the isc and it is good, and the caps on the ecu aren't leaking, is there anything else i could try? anyone?

 

[Eclipse45150]

Hey bud, if your problem isnt fixed yet take it up to autozone or a place near you that can test the alternator, a lot can do it for free. I was havin the same prob with mine last year, ended up needing an alternator and put in a spare battery and isolator for my accessories. Please note though, when they test it make see if they will test if for you with all of your usual load (the accessories you usually run) because it may not be pulling as many amps with these parts off.

If your alternator is good one way to see if a spare battery would be the route to check because it can be costly is get the manuals from your accessories and find out how many amps are being used by each one. Total them up, a stock alternator for a turbo eclipse can handle about 75 amps, if the total is more than this, or at least a decent amount close to 75 then needing a second battery is probably what you need.

Let me know if this helps ya or you got any more questions